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ea82t - beating a dead horse


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First off, I know... really I know... I shouldn't be dumping money into this motor.. Recipe for disaster or deliverance?


defeating HG issues:

o-ring block (and/or heads) + felpro permatorques
head studs (paeco studs - arp nuts)

keeping her cool:
2 row radiator (or wrx rad if I can fit it)
beefy oil cooler

huge bypass filter for extra capacity
tmic or awic (air water might be better for rallyx)

dual electric fans (clutch fan delete)

better fueling:
walbro 255l inline fuel pump
larger injectors (240sx?)
symmetrical fuel lines/rails

piggyback/standalone (emanage or megasquirt)

innovate wideband o2


other goodies:

forged pistons (keep 7.7:1?)
spider intake

more reliable turbo:

 -I have a td04 + uppipe/downpipe but not sure that the best fit

 -was offered a vf11 for free, with no shaft play (might spool faster?)

air oil separator
custom exhaust header, unless I can find a TWE one. (keeping about the same diameter for spool/torque)

 

Anything I am missing anything?

 

Why do I like to learn everything the hard way?

Edited by Ibreakstuff
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I'm not an authority, but here are a few pointers:

 

The clutch fan is primarily for the A/C subsystem, so unless you keep A/C, you can just delete it altogether and run only the main electric fan. If you do delete A/C, you'll want to replace the alternator with one of the double-pulley types if possible and run two belts to ensure the ancillaries are driven properly. If you decide to go with two electric fans, you'll want to install a higher-amperage alternator; search for "Maxima alternator" on here. Really it's a worthwhile upgrade regardless, but a necessity if you increase the demand on the car's weak stock electrical system.

 

As for the radiator, the Spectra CU1099 is a full-metal dual-row radiator. It's designed for the XT and the top mounts won't line up properly on other cars (like my RX, anyway), but the mounts are just spot-welded in place so they should be easy to move compared to modifying an EJ radiator.

 

The spider intake is cool and all, but it's kind of difficult to work with: it sits over a number of components, so you'll have to remove it to get to certain things (FPR, knock sensor, AAV, TWS/ECT) whereas the flat manifold is relatively easy. I have yet to see anything, but the ultimate test would be to build a good EA82T with the flat manifold and dyno it, and then swap on the spider manifold and dyno it. I don't think there would be enough of a gain to be worth the hassle unless you're running a fully modified setup already.

 

If you're changing the turbo you may as well try to get a custom exhaust at the same time; you'll likely have to change the turbo flanges regardless, so a custom front and downpipe wouldn't be much more work. Try to improve the front pipe's flow (it has a T sort of junction at the RH head, which can't be efficient). Also, go with a larger diameter downpipe and try to get a freer-flowing cat while you're at it.

 

You'll probably want a BOV. Unless you move to a MegaSquirt with MAP at the same time, you'll want a plumb-back type; the stock system uses MAF and you'll upset your AFR if you use an atmospheric BOV. There's a cyndrilical reverberator of some type off the side of the main air intake hose between the MAF sensor and the turbo that would be perfect for accepting a BOV return hose.

 

Ultimately I'd like to custom-build an A2W charge cooler to sit where the stock air cleaner resides, with a remote radiator in front of the car or anywhere else with space and good air flow. I can't recommend anything prefab like a TMIC because I want to keep my car stock-looking. I'm all about being subtle with my speed, so I forego the stickers and scoops and loud noises and outlandish colors (though I do repaint rusty engine parts in GM Blue).

 

Also, you'll probably want to look at a set of Delta cams (Torque or HP).

 

I also like to experience things myself, which is why I don't really like my XT anymore. I still love my RX.

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Thanks for the tips mdcc2010!

 

Adding more things to the "do more research" list lol.  :)

I'll look into a higher amp alt and that 2 row radiator.

 

Just thinking based on EJ technology, wouldn't the larger plenum and long runners on the spider be a definite advantage? I guess if the bottleneck is in the heads neither would have an advantage. I know that EJ NA intakes breathe a lot better with supporting mods and larger turbos, but at what point does it become beneficial is the question. I do see you point about getting to things, I don't mind that much tho, just an excuse to get out in the garage.

 

Yep, I'm looking to get a custom header/up made so I can fit a EJ downpipe. It would be nice if one of those TWE headers fell into my lap. Deciding on which turbo has been puzzling me too. The 3 easiest options would be a t035 (forrester), vf11 (free from a friend), or the td04l I have sitting around. The t035 would spool a lot faster, but the other 2 are free lol.

 

I was planning on doing a MAF delete or at least have MAP take over under throttle. But I still need to build a MS and figure out which is best for me, before I start going edward scissor-hands on the wiring.

 

And I agree, AWIC sounds pretty awesome. It would probably be ideal for rallycross (short runs). I hate the idea of a hood scoop but I've been pondering an AWIC setup with a radiator mounted like a tmic and a reservoir to hold a larger capacity of water. I'm not too into stickers and BOV noises either, but I'm definitely tempted to cut a hole in the hood.

 

Some torque cams could be nice. I don't really care about top end hp, I want the power down low.

 

I'm not an authority, but here are a few pointers:

 

The clutch fan is primarily for the A/C subsystem, so unless you keep A/C, you can just delete it altogether and run only the main electric fan. If you do delete A/C, you'll want to replace the alternator with one of the double-pulley types if possible and run two belts to ensure the ancillaries are driven properly. If you decide to go with two electric fans, you'll want to install a higher-amperage alternator; search for "Maxima alternator" on here. Really it's a worthwhile upgrade regardless, but a necessity if you increase the demand on the car's weak stock electrical system.

 

As for the radiator, the Spectra CU1099 is a full-metal dual-row radiator. It's designed for the XT and the top mounts won't line up properly on other cars (like my RX, anyway), but the mounts are just spot-welded in place so they should be easy to move compared to modifying an EJ radiator.

 

The spider intake is cool and all, but it's kind of difficult to work with: it sits over a number of components, so you'll have to remove it to get to certain things (FPR, knock sensor, AAV, TWS/ECT) whereas the flat manifold is relatively easy. I have yet to see anything, but the ultimate test would be to build a good EA82T with the flat manifold and dyno it, and then swap on the spider manifold and dyno it. I don't think there would be enough of a gain to be worth the hassle unless you're running a fully modified setup already.

 

If you're changing the turbo you may as well try to get a custom exhaust at the same time; you'll likely have to change the turbo flanges regardless, so a custom front and downpipe wouldn't be much more work. Try to improve the front pipe's flow (it has a T sort of junction at the RH head, which can't be efficient). Also, go with a larger diameter downpipe and try to get a freer-flowing cat while you're at it.

 

You'll probably want a BOV. Unless you move to a MegaSquirt with MAP at the same time, you'll want a plumb-back type; the stock system uses MAF and you'll upset your AFR if you use an atmospheric BOV. There's a cyndrilical reverberator of some type off the side of the main air intake hose between the MAF sensor and the turbo that would be perfect for accepting a BOV return hose.

 

Ultimately I'd like to custom-build an A2W charge cooler to sit where the stock air cleaner resides, with a remote radiator in front of the car or anywhere else with space and good air flow. I can't recommend anything prefab like a TMIC because I want to keep my car stock-looking. I'm all about being subtle with my speed, so I forego the stickers and scoops and loud noises and outlandish colors (though I do repaint rusty engine parts in GM Blue).

 

Also, you'll probably want to look at a set of Delta cams (Torque or HP).

 

I also like to experience things myself, which is why I don't really like my XT anymore. I still love my RX.

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Motor is coming out next week, the first task will be taking measurements for head studs and pistons. I would like to find a more common arp stud size and just install some thread inserts (time serts or full torque FST/FSD) . If that is not possible, I'll order some 11mm studs from paeco. Its odd that paeco's flanged nuts are so expensive too, I'll probably just buy arp nuts and washers.

 

Sleep time! I have a full day of errands to run tomorrow.

Edited by Ibreakstuff
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Sounds like you have it fairly well thought out already. I had a list of stuff I wanted to do, but I have four cars to keep up with ('87 XT Turbo, '91 Civic, '88 RX, '88 RX-7, in order of most to least broken) so it's kind of more a fix-what's-broken/get-it-running kind of game with my Subarus than it is a performance mod thing right now, especially since it's relatively difficult to get parts for them vs. my other cars. Ultimately I'd like to put a MegaSquirt system in my 'Rus with switchable boost/fuel maps, slightly larger turbo (probably another VF-series or a Garrett variable nozzle turbo if I can get one cheap), A2W charge coolers, and forged internals. I don't plan on pushing more than 180HP out of them (100HP/L is my ideal with most cars) so I'm not too worried about HG issues; RAM Performance may be able to supply more robust gaskets, so I'd check them out before I default to the Felpros. I'd also like to rebuild the transmissions and put taller 4th and 5th gears in both cars and a shorter Lo range on the RX (all parts sourced from 5-spd SPFI boxes). Of course I'd also need to rebuild the RX's LSD if I can find the parts...

 

As for the spider manifold, yes it likely flows a bit better, but most of the benefits will be felt on an NA car because the engine has to work to pull air into the cylinders, whereas a turbo engine will be forcing an increased volume of air at a certain pressure into them; you'd probably only notice a real difference on an EA82T after extensive mods, so for me it would be an optional install once I have everything else built and the MS installed with a base map. I like being able to keep the spare tire up front on my RX because it wastes a huge amount of cargo space to keep it in the back, so I'll keep the flat manifold on it. Anyway, as I noted earlier, nobody has done a proper flow test or a dyno comparing the two manifolds on the same block, and the FSM for my '87 XT with a spider manifold and my '88 RX with the flat manifold both specify the same power numbers; it's not worth it to me. Also, the spider manifold has a different TPS vs. the flat manifold (spider has an extra wire or two and is more expensive), so that's something to watch out for; I'm not sure if one can bolt on in place of the other.

Really it's kind of like the electric fan vs. clutch fan argument on my RX-7: a properly functioning clutch fan will draw no more power from the engine than an electric fan of the same CFM rating, and nobody has ever properly measured the CFM rating of the stock fan, so it's a crapshoot as to whether your new fan is close to the stock fan's rating. Plus, now your alternator will have to run the efan, transferring the power draw on the engine from the fan itself to the alternator. At most you'll gain a small amount of throttle response by ditching the clutch fan; at worst, you'll overtax your electrical system if you don't upgrade the alternator and properly wire up the new efan. If you do a huge amount of other mods at the same time (i.e, a rebuilt engine with loads of performance parts), then yeah, a conversion to an efan would probably be a good idea and help squeeze out that last ounce of power, however minute it may be. On its own, however, you won't notice too much of a difference unless you had a broken clutch fan to start with.

 

If I were in a different phase of my life I would consider doing the dyno comparison stuff myself, but as it is I don't have the time, money, space, or other resources. Maybe when I'm out of the military I'll be able to do so... in 15 years.

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Lol, well I don't claim to be anything other than a novice with a thirst for knowledge. Excellent resume of cars you have there there, well except that honda but I won't hold that against you haha.

 

I spoke to RAM about pistons, but they only have .02 over @ 9.5:1, which wouldn't be too high with proper tuning but I would rather something around 8-9:1. I will have to inquire about HG's to see what they use. I've decided not to oring the block until it becomes a problem, I think head studs themselves might be enough. My hp goal are not much higher than you, but I plan to rallyx the car and i'm pretty hard on them while racing. I broke my wrx so many times ($$$) that I realized I needed to take a step back.

 

I took apart a blown DR (stripped 2nd gear) in order to get more familiar with it, I was very surprised how similar they are to EJ boxes. That would be a cool mod for the trans, more of a wheeling setup right? I believe rebuild kits for the LSD can be found through nissan still. There is a great write up in the Dime Quarterly archives explaining how to rebuild them in detail too (the dime is a datsun 510 zine).

 

I'll hang on to the original flat intake, I was planning on some dyno time for tuning the ESM. If I do, I'll test it out and see. :)

 

Not sure why I always had the (mis)conception that clutch fans robbed more power than efans. I've always hated them on the fords I have owned, mainly because it was such a pita to remove them lol.

 

Thanks for serving! What branch/job?

 

Sounds like you have it fairly well thought out already. I had a list of stuff I wanted to do, but I have four cars to keep up with ('87 XT Turbo, '91 Civic, '88 RX, '88 RX-7, in order of most to least broken) so it's kind of more a fix-what's-broken/get-it-running kind of game with my Subarus than it is a performance mod thing right now, especially since it's relatively difficult to get parts for them vs. my other cars. Ultimately I'd like to put a MegaSquirt system in my 'Rus with switchable boost/fuel maps, slightly larger turbo (probably another VF-series or a Garrett variable nozzle turbo if I can get one cheap), A2W charge coolers, and forged internals. I don't plan on pushing more than 180HP out of them (100HP/L is my ideal with most cars) so I'm not too worried about HG issues; RAM Performance may be able to supply more robust gaskets, so I'd check them out before I default to the Felpros. I'd also like to rebuild the transmissions and put taller 4th and 5th gears in both cars and a shorter Lo range on the RX (all parts sourced from 5-spd SPFI boxes). Of course I'd also need to rebuild the RX's LSD if I can find the parts...

 

As for the spider manifold, yes it likely flows a bit better, but most of the benefits will be felt on an NA car because the engine has to work to pull air into the cylinders, whereas a turbo engine will be forcing an increased volume of air at a certain pressure into them; you'd probably only notice a real difference on an EA82T after extensive mods, so for me it would be an optional install once I have everything else built and the MS installed with a base map. I like being able to keep the spare tire up front on my RX because it wastes a huge amount of cargo space to keep it in the back, so I'll keep the flat manifold on it. Anyway, as I noted earlier, nobody has done a proper flow test or a dyno comparing the two manifolds on the same block, and the FSM for my '87 XT with a spider manifold and my '88 RX with the flat manifold both specify the same power numbers; it's not worth it to me. Also, the spider manifold has a different TPS vs. the flat manifold (spider has an extra wire or two and is more expensive), so that's something to watch out for; I'm not sure if one can bolt on in place of the other.

Really it's kind of like the electric fan vs. clutch fan argument on my RX-7: a properly functioning clutch fan will draw no more power from the engine than an electric fan of the same CFM rating, and nobody has ever properly measured the CFM rating of the stock fan, so it's a crapshoot as to whether your new fan is close to the stock fan's rating. Plus, now your alternator will have to run the efan, transferring the power draw on the engine from the fan itself to the alternator. At most you'll gain a small amount of throttle response by ditching the clutch fan; at worst, you'll overtax your electrical system if you don't upgrade the alternator and properly wire up the new efan. If you do a huge amount of other mods at the same time (i.e, a rebuilt engine with loads of performance parts), then yeah, a conversion to an efan would probably be a good idea and help squeeze out that last ounce of power, however minute it may be. On its own, however, you won't notice too much of a difference unless you had a broken clutch fan to start with.

 

If I were in a different phase of my life I would consider doing the dyno comparison stuff myself, but as it is I don't have the time, money, space, or other resources. Maybe when I'm out of the military I'll be able to do so... in 15 years.

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